Answer:
The mechanical advantage of a machine is the ratio of the load (the resistance overcome by a machine) to the effort (the force applied). For an ideal (without friction) mechanism, it is also equal to: There is no unit for mechanical advantages since the unit for both input and output forces cancel out.
Explanation:
Answer:
Base units are defined units based on specific objects or events in the physical world. Derived units are defined by combining base units.
Base units are defined by a particular process of measuring a base quantity whereas derived units are defined as algebraic combinations of base units. For example, length is a base quantity in both SI and the English system, but the meter is a base unit in the SI system only.
The period of a wave is the time it takes the wave to complete one cycle (at a fixed location).
So if a wave completes one cycle in <em>2 seconds</em>, then that is its period.
Answer:
Given that refractive index of the material is √2. i.e. n = √2. Hence, critical angle for the material is 45°
Answer:
The speed of the electron is 1.371 x 10⁶ m/s.
Explanation:
Given;
wavelength of the ultraviolet light beam, λ = 130 nm = 130 x 10⁻⁹ m
the work function of the molybdenum surface, W₀ = 4.2 eV = 6.728 x 10⁻¹⁹ J
The energy of the incident light is given by;
E = hf
where;
h is Planck's constant = 6.626 x 10⁻³⁴ J/s
f = c / λ

Photo electric effect equation is given by;
E = W₀ + K.E
Where;
K.E is the kinetic energy of the emitted electron
K.E = E - W₀
K.E = 15.291 x 10⁻¹⁹ J - 6.728 x 10⁻¹⁹ J
K.E = 8.563 x 10⁻¹⁹ J
Kinetic energy of the emitted electron is given by;
K.E = ¹/₂mv²
where;
m is mass of the electron = 9.11 x 10⁻³¹ kg
v is the speed of the electron

Therefore, the speed of the electron is 1.371 x 10⁶ m/s.